When the EPA issues rules in 2014 governing carbon pollution from existing power plants, there will be at least one significant difference from the proposed regulations for future plants it released last week: Carbon capture and sequestration probably will not be part of the equation.

EPA Administrator Gina McCarthy said Monday that CCS technology works well when it is designed into new plants, but “it is not seen, at least at this stage, as an add-on.” Speaking at a breakfast hosted by the Christian Science Monitor, McCarthy added that CCS  for existing plants “doesn’t seem appropriate at this stage.”

CCS involves capturing the carbon dioxide emitted by power plants and pumping it into underground formations. That is the technology that EPA envisions any new coal-fueled power plants using to stay under the new limits for carbon emissions the agency issued Thursday. The effort is aimed at reducing the amount of heat-trapping greenhouse gases in the atmosphere that have contributed to the warming of the planet.

McCarthy repeated her view that last week’s regulations “were the application of currently existing law as it was supposed to be applied,” a reference to the Clean Air Act. “The Supreme Court told us carbon should be looked at as a pollutant,” she added.

The new standard would require future coal plants to emit no more than 1,100 pounds of carbon dioxide per megawatt hour. To meet the new limit, coal plants would have to capture and store 20 to 40 percent of the carbon they produce. Some mining and business interests have complained that the administration is waging a war against coal, and that CCS technology has not been adequately demonstrated for normal use by power plants.

McCarthy said in an interview last week that “clearly the technology is available. It’s been fully demonstrated.”